It’s not unheard of for fantasy geeks to debate the merits of Diagon Alley versus King’s Landing, Hermione Granger versus Daenerys Targaryen. But French filmmaker Patrice Leconte may be the first to wonder whether Severus Snape or Robb Stark would emerge triumphant in a battle for the heart of Iron Man 3 star Rebecca Hall.

Okay, so that probably wasn’t really Leconte’s aim in making the pre-WWI romance A Promise. But it’s more fun if you imagine it was. Alan Rickman plays a successful factory owner, whose health problems force him to increasingly rely on his assistant (Richard Madden). Meanwhile, said protege is falling for the older man’s wife, played by Hall. Watch the first trailer after the jump.